I've read over some of the posts on strollers in the parks and was curious as to your opinions. I see many of you use the rental strollers or double strollers. I wish I could spend the extra money on one of the nice swivel wheel double strollers but all my budget is going into 10 days at the World! Here's my question: My wife and I are taking my 3 yo DD and 1 yo DD for 10 days with hoppers in May. We have a non-swivel wheel jog stroller which I gather is a bad idea in the parks. Should we spend $100 on a cheaper double stroller or just get two inexpensive and lightweight umbrella strollers? It seems the Umbrella strollers would be relatively mobile and easy to get onto buses & monorails? I guess I'm a little suprised that everyone seems to use one big double stroller instead of pushing two small lightweight singles? Is there something I'm not thinking of? Thanks for your help I definately don't want unhappy kido's all week!